Table 1.

TLR-mediated responses and potential applications for therapeutic immunomodulation^*

TLR-mediated responses	Applications	Agents	TLRs involved**	Refs.
Antimicrobial molecules (e.g., nitric oxide, β- defensins)	infection control	agonists	TLR2, TLR4	(233)
Type I interferons	antiviral immunity	agonists	TLR-3, -4, 7-, 8-, and -9	(15, 70, 155)
Adjuvant activities (e.g., upregulation of costimulatory molecules)	vaccination	agonists	TLR2, TLR4, TLR9	(106, 231, 245)
Regulatory effects on antigen-presenting cells or lymphocytes	skewing of the T cell subsets to the desired type of response	agonists or antagonists	TLR2, TLR4, TLR9	(60, 64, 73, 137)
Inflammatory mediators (e.g., TNF-α, IL-1β)	chronic inflammatory diseases, septic shock	antagonists	TLR4, TLR2/1, TLR2/6	(43, 140, 141, 154)
Evasion or subversion (of TLR signaling) by pathogens	counteraction of microbial immune evasion/subversion	agonists or antagonists	TLR2, TLR4	(40, 49, 89, 157, 207)

^*Examples selected on the basis of their relevance to periodontal host modulation.

^**Potentially more TLRs are involved; mentioned were only those for which strong evidence exists.